Next,heplannedtobuildhisownplaneandflyalonearoundtheworld. Buildingtheplanewasdifficult.Irvingaskedmorethan50companiesforairplaneparts. Mostsaidno,buthepersisted(顽强地坚持)inasking.Threeyearslater,hehadpartsworth $300,000.Columbia,anairplanecompany,agreedtobuildaplaneusingtheparts.Soon,his airplanewasreadyto...